Hiccup has received a strange book full of knowledge about dragons. Finding a potion that grants strength and the designs for a special arrow, he sets out to slay the Night Fury. Except now he finds himself slowly losing his humanity bit by bit... while simultianously changing the Night Fury into just an ordinary boy. And then things got even stranger.

Hiccup didn't see the point in stopping Astrid as she ran off towards his village—towards his father—with his most desperately protected secret. He was leaving anyway. A coming-of-age tale. Deviates from movie. Borderline bromantic-comedy.